Artificial limb



Aug. 11, 1931. 1 L HOY ARTIFICIAL LIMB Patented Aug. 11., i 1931Um'rlso,STATES LYMAN LORRAINE HOY, F TILLAMOOK, OREGON ARTIFCIAL LIMBApplication led November 30, 1929. Serial N'o. 410,795.

VThis invention relates to an artificial limb, more particularly to anankle oint therefor, and has for its primary object to provide, in amanner as hereinafter set forth, an articial limb wherein the foot andleg portions may have relative movement therebetween which issubstantially a simulation of such movement in a natural limb.

A' further object of the invention is to 1o provide an artificial limbwherein the foot and leg portions are resiliently connected together ina manner to provide for substantially the same ease and springiness inthe movement of the artificial limb as in a natural limb. v

A further object ofthe invention is to provide an artificial limbwherein the foot and leg portions are connected together in a manner toinsure silent relative movement therebetween.

With the foregoing and. other objects in view, the' invention consistsof the novel construction, combination and arrangement of parts ashereinafter more particularly described, and as illustrated in theaccompanying drawings wherein is shown an embodiment of the invention,but` it is to be understood that the description and drawings'are to betaken as illustrative and thatthe invention is intended to be limitedonly by the scope of the claims hereunto appended.

In the accompanying drawings-in which like numerals are employed todesignate like parts throughout the same: c

Figure 1 is a central vertical section through an artificial limbconstructed in accordance with this invention. v

Figure 2 is a vertical sectiontaken at a point indicated by the line 2-2of Figure 1.

Figure 3 is a bottom` plan of the limb.

Figure 4l is an enlarged perspective'view of the block interposedbetween the footv and leg portions of the limb. f

Referringto therdrawings in detail, the numerals 1,' 2 and 3respectivelyjdesignate thev upper leg'portion, the lower leg portion,and the foot portion of myfimprovedartiiicial limb. Inthe embodimentshown herein the upper leg portion lis of'hollow construction and may besecured to the lower leg` portion 2 in any suitable manner.

Formed in the lower face of the lower leg portion 2 is a recess having apair of side wallsl and a top wall 5. The side walls 4 are slightly.concaved and the top wall 5 is also slightly concaved from side to ysideand merges intothe side walls 4c. From front to back the top wall 5 isof arcuate form and extends to the lower vface of the lower leg portion2 at its forward and rearward extremities whereby the top wall 5alsoprovides the Vfront and back walls of the recess. Disposed withinthe recess is a lining Y6 which snugly engages the walls thereof. c

Formed inthe upper faceV of the foot portion 3 is a recess having. abottom wall 7, va front wall 8, and a rear wall 9. The front and rearwalls 8 and 9 are substantiallystraight and extend in continuation ofthe topwall 5 of the recess in the lower leg portion 2 when such legportion and the foot portion 3 are in assembled relation.

The bottom wall 7 of the foot portion recess is convex in shape fromfront to back and arcuate in shape from side to side and extends at itssides to the upper face of the foot portionthereby also providing theside walls. of the recess. As shown in Figures 1 andV 2, the lower faceof the lower leg Aportion 2 and upper face of thefoot portion 3divergein a direction away from the recesses when theleg and footportions are in assembled relation.

Disposed in the above described lrecesses is a block 10 which ispreferably formed of aluminum and the front, back and topl of which arecontinuous and conform in contourto the top wall 5 and the front andback ywalls 8 and 9 ofthe recesses., Adjacent the .top thereof, thesides of the block l0, as indicated at ll, conform in cont-our with theside walls 4 of the recess in the lower leg portion 2. The remainingside portions ofthe block 10 are concaved as indicated at l2 and mergeinto the bottom of the blockV which is also concaved as indicated atlf'from front to back. From side to side the bottom of the block lO isarcuist ate to conform in contour with the bottom wall 7 of the recessin the upper face of the foot portion 3. Interposed between the blockand the recess inthe foot portion 3 is a lining 14 which snugly engagesthe walls of such recess. The linings 6 and 14 are in direct contactwith the block 10 and may be treated with graphite or other suitablelubricant.

Formed in the upper face of the lower leg portion 2 is a plurality ofrecesses, in the present instance four in number and designated by thenumerals 15, 16, 17 and 18. Extending from the bottoms of the recesses15, 16, 17 and 18 is a plurality of elongated openings 19 which extendthrough the lower face of the leg portion 2. EX- tending in longitudinalalignment with the openings 19 when the leg and foot portions of thelimb are in assembled relation is a plurality of elongated openings 20,the lower ends of which open into a plurality of recesses formed in thelower face of the foot portion 3 and designated by the numerals 21, 22,23 and 24 respectively. The openings 19 gradually increase in diametertowards the lower face of the leg portion 2 and the openings 2Ogradually increase in diameter towards the upper face of the footportion 3. Associated with the recesses 15, 17, 18, 21, 23 and 24 andextending through each of the aligned openings 19 and 2O opening intosuch recesses is a rod 25 which is threaded at its upper end asindicated at 26. rlhe upper end of each rod 25 is disposed within one ofthe recesses 15, 17 and 18 formed in the upper face of the lower legportion 2 and is provided with a nut 27 which bears against a washer 28.Encircling the rod 25 is a coiled spring 29, the lower end of whichabuts against the bottom wall of the recess and the upper end of whichabuts against a resilient washer 30, preferably formed of rubber, whichis interposed between the spring 29 and washer 28.V The lower end'ofeach of the rods 25 is provided with a head 32 which is preferably`formed with Ya slot 33 forthe accommodation of a tool, such as a screwdriver. Each head 32 is disposed within one of the recesses 21, 23 and24 in the lower face of the foot portion 3 and interposed between thehead and the top wall of such recess is a rigid washer 34 and aresilient washer 35,

the latter of which is preferably formed of rubber.

Cneof the rods 25 is'disposed forwardly of the block 10, and one on eachside thereof. l

Associated with the recesses 16 and 22 is a rod 25 which extends throughthe aligned openings 19 and 20 opening into such recesses and thelowerend of which Vis identical with the lower ends of the rods 25. Threadedon the upper end of 'the'rod 25 is a nut 27 which is disposed within therecess 16. Encircling the rod 25 is a resilient sleeve 31, preferablyformed of rubber, which seats on the bottom wall of the recess 16.Interposed between the sleeve 31 and nut 27 is a washer 28.

The springs 29and resilient sleeve 31 assembled on the rods l25 and 25respectively resiliently hold the lower leg portion 2 and foot portion 3in assembled relation and by tightening the nuts 27 and 27 the tensionof the springs 29 and sleeve 31 may be regulated as desired. Owing tothe shape of the lock 10 and of the recesses formed in the lower face ofthe lower leg portion 2 and in the upper face of the foot portion 3, thelatter is freely movable relative to the lower leg portion 2 from sideto side and from front to back. Due to the gradually increasing diameterof the openings 19 and 20Y towards the lower face of the leg portion 2and the upper face of the foot portion 3 respectively, considerablelateral movement of the rods 25 may be had without coming in contactwith the walls of the openings, thereby preventing the possibility ofany noise from such movement. Due to the resilient washers 35 and 30,any possibility of noise is prevented from the longitudinal movement ofthe rods 25 or the springs 29.

It will be perceived that the peculiar `formation of the block 10 and ofthe recesses in the l foot and lower leg portions within which the blockis seated provides the latter with a pair of right angularly disposedaxes, one of which is superimposed above the other'as in a natural anklejoint. lVhile free Vlateral movement of the foot portion 3 with respectto the block, and free forward and rearward movement of the leg portion2 with respect thereto is provided, a relatively large bearing surfacebetween the block and each of the lower leg and foot portions isprovided and any relative rotary movement between the foot and legportions is prevented.

InA the event of an extremely low amputation, the recesses in the upperface of the lower leg portion and in the lower face of the foot portionmay be reversed, in which event the rods 25 and 25 would also bereversed so as to seat the springs 29 and sleeve 31 in the recesseswithin thefoot portion.

It is thought that the many advantages of an artificial limb inaccordance with this invention will be readily apparent, and althoughthe preferred embodiment of the invention is as illustrated anddescribed, it is to be understood that various changes in the size,shape and arrangement of parts may be resorted to, so long as suchchanges fall within the scope of the invention as defined in theappended claims.

What claim is A 1. Anv artificial limb comprising, a leg portion formedin its lower face with a recess having a pair of substantially verticalside walls and further having a concave top wall merging at its sideswith the side walls and extending to the lower face of said leg portionat its forward and rearward extremities, a foot portion formed in itsupper face with a recess having substantially vertical front and backwalls and further having a convex bottom wall merging with the front andback walls and extending at its sides in a concave plane to the upperface of said foot portion, an anti-friction lining for each of saidrecesses conforming in contour therewith, a block engaging said liningsand conforming in contour therewith when said portions are in assembledrelation, said block being movable in a lateral arc relative to one ofsaid linings and movable in a forward and rearward arc relative to thevother of said linings, and resilient means for holding said portions inassembled relation.

2. An artificial limb comprising, a leg portion formed in its lower facewith a recess having a top wall concave from front to rear, a footportion formed in its upper face with a recess having a bottom wallconcave from side to side, said bottom wall being convex from front torear, an anti-frietion lining for each of said recesses conforming incontour therewith, a block engaging said linings and conforming incontour therewith when said portions are in assembled relation, saidblock being movable in a lateral, vertical arc relative to one of saidlinings and being movable in a forward and rearward, vertical arcrelative to the other of said linings, and resilient means for holdingsaid portions in assembled relation.

8. A rigid block for disposition between the leg and foot portions of anartificial limb, said block having a continuous front, top and rear faceof convex contour and further having a pair of substantially verticalside faces merging into said continuous face, said block further havinga bottom face extending between said side faces in a convex plane andfurther extending between the end portions of said continuous face in aconcave plane.

In testimony whereof, I affix my signature hereto. l

LYMAN LORRAINE HOY.

